//-----------------------------------------------------------------------
// -----------------------------------------------------------------------
// file="ExpSyntaxAnalyzer.OperatorParser"
// Project: StgSharp
// AuthorGroup: Nitload Space
// Copyright (c) Nitload Space. All rights reserved.
//     
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
//     
// -----------------------------------------------------------------------
// -----------------------------------------------------------------------
using StgSharp.Script;
using StgSharp.Script.Express;

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

using ExpKeyword = StgSharp.Script.Express.ExpressCompile.Keyword;

namespace StgSharp.Model.Step
{
    internal partial class StepExpSyntaxAnalyzer
    {

        public int CompareOperatorPrecedence(Token left, Token right)
        {
            ExpressCompile.TryGetOperatorPrecedence(left.Value, out int leftPrecedence);
            ExpressCompile.TryGetOperatorPrecedence(right.Value, out int rightPrecedence);
            return leftPrecedence - rightPrecedence;
        }

        public bool TryGenerateUnaryNode(Token t, out ExpSyntaxNode node)
        {
            ExpSyntaxNode operand = GetNextOperandCache();
            switch (t.Value)
            {
                case ExpKeyword.UnaryPlus:
                    node = ExpUnaryOperatorNode.UnaryPlus(t, operand);
                    return true;
                case ExpKeyword.UnaryMinus:
                    node = ExpUnaryOperatorNode.UnaryMinus(t, operand);
                    return true;
                case ExpKeyword.Not:
                    node = ExpUnaryOperatorNode.UnaryNot(t, operand);
                    return true;
                default:
                    node = ExpSyntaxNode.Empty;
                    return false;
            }
        }

        /// <summary>
        ///   WARNING: This method cannot process INDEXOF, FUNCTION CALLING, LOOP and any ENDING
        ///   SYMBOLS.
        /// </summary>
        private ExpSyntaxNode ConvertAndPushOneOperator(Token op)
        {
            switch (op.Flag)
            {
                case TokenFlag.Symbol_Unary:
                    TryGenerateUnaryNode(op, out ExpSyntaxNode? node);
                    _cache.PushOperand(node);
                    return node;
                case TokenFlag.Symbol_Binary:
                    TryGenerateBinaryNode(op, out node);
                    _cache.PushOperand(node);
                    return node;
                case TokenFlag.Member:
                    _cache.PopOperand(out _, out ExpSyntaxNode? p);
                    StepEntityInitCaller caller = StepEntityInitCaller.CreateCaller(op.Value);
                    node = ExpFunctionCallingNode.CallFunction(op, caller, p);
                    _cache.StatementsInDepth.Push(node);
                    return node;
                default:
                    throw new NotImplementedException();
            }
        }

        private bool TryGenerateBinaryNode(Token t, out ExpSyntaxNode node)
        {
            /*
            ExpSyntaxNode right = GetNextOperandCache();
            ExpSyntaxNode left = GetNextOperandCache();
            /**/
            switch (t.Value)
            {
                case "=":
                    ExpSyntaxNode right = GetNextOperandCache();
                    ExpSyntaxNode left;
                    if (right is ExpTupleNode tuple)
                    {
                        right = StepComplexEntityNode.FromTuple(tuple);
                        left = GetNextOperandCache();
                    } else
                    {
                        left = right;
                        right = _cache.StatementsInDepth.Pop();
                    }

                    node = ExpBinaryOperatorNode.Assign(t, left, right);
                    return true;
                default:
                    node = ExpSyntaxNode.Empty;
                    return false;
            }
        }

    }
}